It was after our calc lecture. Everyone was leaving the hall while my gf starts to stroke me over my pants. When everyone leaves the room she unzips my pants and takes me in her mouth. I have a sudden rush of nerves and pleasure. I push her head down and moan. She knows she only had about 20 mins until the next class so she climbs on top of me, taking her leggings off. She slips my cock between her panties and we start going at it— hard. After a while i turn her over and bend her over the seats in front of us. We’re moaning pretty loud at this point and I’m scared we’re gonna get caught but i like it. I grab her hair and thrust some more. The situation gets me really fucking wet and I’m about to cum. I pull out and she turns around to blow me. She pushes me down on the seat and starts sucking my cum out of me. We hear the door open as im finishing in her mouth. I try my hardest not to make noise as we’re cleaning up. My gf sits down next to me and puts her pants back on and we stealthily leave the (almost) empty lecture hall.